types and type algebra in sbcl and cmucl - comp.lang.lisp

Message from discussion types and type algebra in sbcl and cmucl
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From: jimka <ji...@rdrop.com>
Newsgroups: comp.lang.lisp
Subject: Re: types and type algebra in sbcl and cmucl
Date: Thu, 18 Dec 2008 13:32:52 -0800 (PST)
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I'm interesting in reading about how the type algebra works and
and how the reasoning about types is done.   How does python
look at code and reach conclusions about the types?  I imagine
it is very complicated, but probably some parts are approachable...

-jim



> The type system used internally in SBCL is exactly the same
> implementation of the ANSI CL type system available to user programs.
> This means that the type system per se is described in Chapter 4 of
> the spec. What this means for user programs is described in section
> 3.2 of the SBCL manual, "Handling of Types". The description of the
> compiler in the paper "Design of CMU Common Lisp", edited by Rob
> MacLachlan, is still largely relevant to SBCL. Chapters 9 and 10
> describe the handling of types, although they may be less than
> comprehensible without reading the preceding chapters on the ICR
> representation.